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Observations of RR Lyrae and X ARIETIS with the IUE satellite.
Bonnell, J. T.; Bell, R. A.
UV spectroscopic observations of RR Lyr and X Ari obtained at high and low dispersion using the LWR and SWP cameras of IUE on Jan. 25-28, 1980, are reported. The data are presented in tables and graphs and compared with the results of synthetic-spectrum calculations based on the VR photometric data of Manduca et al. (1981). Good agreement is obtai…
HD 8358 : a new active chromosphere binary.
Ake, T. B.; Bopp, B. W.; Goodrich, B. D. +5 more
The results of an extensive study of the eighth-magnitude G star HD 8358 employing optical photometry and spectroscopy, as well as UV observations with the IUE satellite, are presented. The star is found to be an active chromosphere binary with orbital and photometric period of 0.516 days. It exhibits photometric variability of 0.1-0.2 mg in V, du…
High-dispersion spectroscopy of the eclipse of epsilon Aurigae at visible and ultraviolet wavelengths.
Ferluga, S.; Hack, M.
Visual observations: The authors report some preliminary results of the study of three photographic spectrograms obtained during the ingress, totality and egress phases and compare them with one spectrogram taken before the start of the eclipse. They describe the characteristics of the "shell" spectrum which are similar to those observed during pr…
Emission by OD in comets
A'Hearn, M. F.; Schleicher, D. G.; West, R. A.
A calculation has been made of the complete fluorescent equilibrium of OD in sunlight including ultraviolet (A-X) transitions, vibrational and rotational transitions (A-A and X-X), and Lambda-doubling transitions in the X state. The dependence on heliocentric radial velocity is strong. No lines of OD are visible in any cometary spectra taken with …
Gamma-ray emission from atomic and molecular gas at intermediate galactic latitudes
Strong, A. W.
Recent developments in the study of the correlations between gamma-rays and local gas tracers are described. COS-B data in the range between b of 10 and 20 deg are analyzed using simultaneous 21-cm and galaxy count data, in order to separate the roles of atomic and molecular gas. The new galaxy-count calibration of Strong (1983) is used, and the r…
EXOSAT observations of NGC 1399 and NGC 1404: Two elliptical galaxies in the center of the Fornax cluster
Mason, K. O.; Rosen, S. R.
Imaging X-ray observations of the Fornax cluster of galaxies centered on NGC 1399 and NGC 1404 are presented. NGC 1399 and NGC 1404, which are separated by about 10 arc minutes, are found to have an unusually high ratio of x-ray to optical flux. We consider the possibility that the x-radiation is produced by hot gas in the cores of the galaxies. W…
IRAS and near-infrared observations of the Seyfert galaxies MCG 8-11-11, MKN 79 and MKN 279.
Roth, M.; Di Cocco, G.; Coe, M. J. +11 more
IRAS-pointed observations and near-infrared photometry of the Seyfert galaxies MCG 8-11-11, Mkn 79 and Mkn 279 are presented. Superimposed on a power law behaviour with α = -1.2, MCG 8-11-11 shows an excess at 25 µm which can be accounted for by black body emission at ≡200K from a dust emitting region of 73 pc or more. Mkn 79 has a single po…
Ultraviolet continuum variability of the quasar 3C273
Ulrich, M. H.; Courvoisier, T. J. -L.
Several quasars show an excess of radiation in the ultraviolet over the power law defined by their infrared/optical continuum. Several authors1-4 have fitted the infrared to ultraviolet spectrum of these quasars with a combination of a power law component, line emission, blends of Fe II lines, Balmer continuum and a black-body component…
The resonance lines of B II and Be II in Hg-Mn stars.
Sadakane, K.; Jugaku, J.; Takada-Hidai, M.
The resonance lines of B II and Be II are analyzed in 25 Hg-Mn stars. The B II line is present in nine (36 percent) stars, and the line is absent in the remaining stars. Strengths of the B II and Be II lines are in accordance with the predictions of the diffusion theory for about half the sample stars. Five Hg-Mn stars show the strong B II line an…
A space-borne plasma analyser for three-dimensional measurements of the velocity distribution
Coates, A. J.; Winningham, J. D.; Johnstone, A. D. +3 more
A new type of plasma analyzer, capable of covering the three-dimensional energy distribution of charged particles from a spinning spacecraft, has been built for the AMPTE and GIOTTO spacecraft. The novel features are the use of 260 deg of deflection in a spherical plate electrostatic analyzer to obtain energy discrimination simultaneously with dis…